1. Field of the Invention
The present invention relates to a testing apparatus, and, in particular, to a testing apparatus capable of replacing flash memory chips quickly and separating signals of the flash memory and the dynamic random access memory (DRAM).
2. Description of the Related Art
Embedded memories, such as embedded multimedia card (eMMC), embedded multi-chip package (eMCP), and card-interface multi-chip package (CiMCP), on a printed circuit board (PCB) are usually packaged with a fine-pitch ball grid array (FBGA) which is usually very close to the core chip, and dedicated FBGA soldering equipment is required for installing and replacing the embedded memories. In addition, repeated soldering operations may easily damage the PCB, the core chip, and the flash memory of the eMMC chip (e.g. NAND flash memory). Generally, an external device is required to install and replace the eMMC/eMCP/CiMCP chip, so that the NAND flash memory of the eMMC chip will not be damaged.
The eMMC chip and a DDR memory are packaged together in an eMCP/CiMCP chip on the PCB. Accordingly, an external device should be used to separate the eMMC signals and DDR memory signals, so that the eMMC chip can be installed and replaced easily. On the PCB, the eMMC device and the eMMC host are connected to each other through the wires on the PCB. Accordingly, an external device should be used to induct the test points of the eMMC signals to test the eMMC signals.
Traditionally, the eMMC/eMCP/CiMCP chip is firstly unloaded from the PCB, and a FBGA socket is installed on the soldering point of the eMMC/eMCP/CiMCP. Thus, the eMMC/eMCP/CiMCP chip can be placed into the FBGA socket. However, there are many electronic components around the soldering place of the eMMC/eMCP/CiMCP chip, and there is no spare space and structure to hold the FBGA socket. Accordingly, a dedicated FBGA socket device should be designed based on the shape of the PCB, and then the eMMC/eMCP/CiMCP chip can be placed into the FBGA socket device, and the dedicated FBGA socket device is fixed onto the PCB. Accordingly, the traditional way may take a very long time to perform the aforementioned operations, and the size of the FBGA socket device is very large, and there are no testing points for eMMC signals.
In addition, there are several disadvantages to the traditional method. For example, (1): the insulation layer of the PCB should be exposed, and some additional wires are soldered onto the PCB to test the eMMC signals. The PCB is usually damaged by the aforementioned operations, resulting in failure of testing eMMC signals. (2) there are NAND flash pins on the eMMC/eMCP/CiMCP chip, but there are no dedicated pins for testing the NAND flash memory on a traditional PCB, so that the NAND flash memory signals cannot be tested on the traditional PCB. (3) the eMMC chip and the DDR memory are packaged together into a eMCP/CiMCP chip, and the signals from the eMMC chip and the DDR memory cannot be separated in the traditional way.